The modern means of reducing waste volume by incineration of huge volumes of sewage sludge or rubbish has created literally growing mountains of ash, typically located near population centers. This ash has both physical and chemical characteristics much different than ash from coal burning utilities. Incinerator ash is composed of much smaller individual particles that produce more fly ash with high air flow for complete combustion. Then, the final ash temperature of bottom ash is not conducive to vitrification, thus, forming cinders or slag. Chemically, the ash from incineration reflects the source.
The composition of incinerator ash shows the effects of industry, commerce and health, as well as domestic activities. There are minute, but measurable, amounts of toxic heavy metals and organics, particularly halocarbons, which are believed to be carcinogenic. The small particle size of incinerator ash makes it undesirable in the environment for more than any toxic effect. This fine ash moves with the wind when dry and suspends and moves with rainfall into streams. Water leaches incinerator ash carrying unwanted wastes into ground water. It is easy to believe that ash from incinerators is at least as obnoxious in the environment as are the dump sites for both rubbish and sewage sludge.
There has not heretofore been provided an effective, economical technique for treatment of ash and waste paper in an environmentally safe manner.
My prior patent, U.S. Pat. No. 4,872,993, incorporated herein by reference, describes techniques for making expanded ceramic particles using waste water containing organic matter and toxic metals. Such patent describes very useful techniques for removing organic matter and heavy metals (both toxic and non-toxic) from waste water streams (both industrial and municipal, for example). However, such patent did not describe manufacture of ceramic particles using ash or waste paper.